I. Field of the Invention
The present invention relates generally to devices for separating seafood of various sizes, and more particularly for separating desired seafood products from unwanted seafood products caught in a net.
II. Description of Prior Art
In commercial as well as recreational fishing which involves the use of large nets, fisherman have always looked for ways of separating the seafood products they desire (mainly shrimp) from those for which they have no use. Given the myriad of sea products retrievable in any one catch, the separating process can take long periods of time while workers divide the desired shrimp or fish from any entrained vegetation or miscellaneous sea life. While some separation can be achieved through a host of devices designed specifically for use with a trawl net during the trawling process, the separating techniques used on the boat itself or on wharves once the boat has reached shore are often times primitive.
Many times, boats will simply empty their catches onto a wharf once they have reached shore, whereupon workers will sift through the catch removing those fish and shrimp that are to be kept. This method promotes premature decomposition of the seafood, invites contamination, and results in pervasive odors in and around the wharf. Another typical separating technique known in the fishing business is the use of a large table having an inclined surface and at least two raised sides to prevent escape of wandering seafood, such as crabs. The upper end of the table is open to allow upward-climbing crabs to leave the table and fall into a waiting container, thus making it easier to pick out the shrimp from the catch. While this device is simple, it is generally very large and hence unsuitable for use on most boat decks. Moreover, it requires much use of manual labor to segregate the seafood, and offers no means of classifying different size seafood into industry-accepted classes.
Another, and perhaps more pervasive, problem with current methods of collecting seafood from nets is that most of the unwanted products are killed in the process of retrieving the desired catch. For example, another common method of separating shrimp from other seafood is to empty the net contents into a vat filled with highly concentrated brine. Exposure to the brine causes the fish, crabs, and other animals to die and rise to the surface of the liquid while the shrimp sink to the bottom. Therefore, once the shrimp are collected, the undesired seafood products are simply wasted rather than returned alive.
The unnecessary killing of unwanted seafood is also the result of attempts to clean the contents of the net prior to dumping the catch into the boat. In many cases, a net filled with a combination of seafood, plant debris and mud will be hoisted from the water and suspended over the deck of the boat. At a point just above the contents of the net, the net will be constricted and tightly tied in order to completely restrict the motion of the seafood within the net, thereby preventing seafood from escaping through the net. Thereafter, this filled portion of the net is placed back into the water and dragged below the surface for some time until most of the mud and debris are washed therefrom. Any crabs and fish caught in the net are thus killed during the washing process, because they are unable to move and circulate oxygenated water into their gill systems.
Most importantly, however, endangered marine turtles which may have also been captured are also killed during the washing process described above. The killing of these turtles has prompted, among other things, federal regulations (37 C.F.R. .sctn..sctn.227.71-227.72) which require certain fishing vessels to incorporate so-called "turtle excluder devices" or "TED's" which allow these turtles to escape the nets prior to retrieval of the net from the water. These regulations have been met with strong resistance from fishermen, primarily because use of the TED's reduces their catch when desired seafood escapes with the turtles, and because the regulations limit the allowable tow time of the trawl. Consequently, any device which would accomplish the live return of turtles and other unwanted seafood into the sea, and thus reduce or eliminate the need for these TED's, would be met with instant and widespread acceptance in the fishing industry.
What is needed, therefore, is a seafood separator device which is still simple to maintain and use, but which includes the ability to quickly separate fish and shrimp into size groups for later processing. In addition, such a device is needed for actual use on the deck of a boat while the boat is at sea so that unwanted sea products may be returned to the sea alive, rather than killed during the cleaning and sorting process. The environmental advantages of returning seafood to the sea alive are that populations of endangered or other non-consumable animals are left intact, and seafood too small to be commercially acceptable are allowed to grow until they may be harvested at a later time. It would also be advantageous to have a device which would allow quick return of the net back into the sea for further trawling without the need to "drag clean" the contents or to modify existing nets for use with turtle excluder devices.